I used 81,6 x 38 R tires. They are big anaugh for my Truck. The rear axle have a bigger groundclearance than the front axle. And only the rear have a pendular suspension. Ok, that isn`t a real suspension. I use rubberbands. Thats easier to build and works good, too. Than the Truck has two speceals.First are lights and seconds is a steeringwheel, powered of an old micromotor.